In Peru, investigators are leaning on van der Sloot to give them information about Holloway's 2005 disappearance in Aruba during a school trip. He has been arrested twice in Aruba and remains the prime suspect, but has never been charged.
Master hackers hired by Peruvian authorities to examine his laptop have reportedly found pictures and other information relating to Holloway.
Investigators in Lima are also pressuring van der Sloot to take them to the hotel where Flores was killed to retrace his steps.
Police investigators told Lima's La Republica newspaper that van der Sloot's bombshell confession came late Monday night when he tearfully admitted that he grabbed Flores by the neck when she began reading articles about him on the Internet.
"I did not want to do it. The girl intruded into my private life," he told investigators, according to La Republica. "She had no right."
"I confronted her," he continued. "She was frightened, we argued and she wanted to get away. I grabbed her by the neck and I hit her."
Dave Holloway, Natalee Holloway's father, told "Good Morning America" Tuesday that search teams had been assembled in Aruba in case Peruvian investigators are able to glean any more information about the teenager's disappearance.
"He's confessed to this one," Holloway said of Flores' death, "and I'd like for him to tell everyone what happened."
Holloway said he's been closely following the Flores case, calling it "deja vu."
"I would just like to say that you know all the pain and suffering that we've gone through, hopefully justice is served this time," he said.
Peruvian authorities have been careful to document every step of their investigation, videotaping every move including a search of his belongings.
Flores' father, Peruvian politician and race car driver Ricardo Flores, told ABC News that van der Sloot's laptop "contains valuable information that may lead to more of Joran's victims."
"I think he killed many others," he said.
Prior to van der Sloot's reported confession, Peruvian authorities released videos of his interrogation and from the hotel where he brought Flores after a night of drinking and gambling.
In the video of his interrogation, van der Sloot can be seen calmly explaining where he's been and what he's carrying, including a laptop, cash from different countries and photos. He even seemed friendly with the officers on his long drive back from Chile to Lima.
When investigators asked him where his credit cards were, van der Sloot answered in broken Spanish.
"I have those back in my hotel in Santiago," he said on the video. "I went up to my hotel room and I saw these things on the Internet and I had to leave quickly."
The calm demeanor van der Sloot showed on the video was a stark contrast to the stunned, even frightened look on his face as he was paraded in front of a media frenzy upon his return to Lima.
On the hotel surveillance video, released this week, van der Sloot can be seen getting his room key from the front desk. Police said they believe Flores was walking behind him, her back to the camera.
Moments later another camera upstairs captured the two walking into van der Sloot's room.
Van der Sloot was captured on camera leaving the hotel alone four hours later, wearing a different shirt and carrying a bag and a backpack.